The present invention relates to novel N-(arylsulphonyl)amino acid derivatives, to their preparation and to pharmaceutical compositions containing them.
These compounds have affinity for bradykinin (BK) receptors. Bradykinin is a nonapeptide belonging, like the decapeptide kallidin, to the class of kinins and which shows physiological activity in the cardiovascular field and as a mediator in inflammation and pain. Several bradykinin receptors are distinguished: the B, and receptors (D. Regoli et. al., Pharmacol. Rev., 1980, 32, 1-46) More precisely, the B2 receptors are the bradykinin and kallidin receptors: they are predominant and are normally found in most tissues; the B1 receptors are the receptors specific for [des-Arg9] bradykinin and for [des-Arg10] kallidin: they are induced during inflammatory processes.
Bradykinin receptors have been cloned for different species, in particular for the human species: B1 receptor: J. G. Menke et al., J. Biol. Chem., 1994, 269 (34) 21583-21586; B2 receptor: J. F. Hess, Biochem. Biophys. Res. Commun., 1992, 184, 260-268.
The reviews: Drug News and Perspectives, 1994, 7 (10), 603-611 and Exo. opin. Ther. Patents, 1995, 5(4), 331-340, give an account on bradykinin-receptor antagonists. Many antagonists described have peptide structures. As bradykinin-receptor antagonists, mention may he made in particular of HOE-140 (F. J. Hock, Brit. J. Pharmacol. 1991, 102, 769-773) for the B2 receptor and [des-Arg9, Leu8] bradykinin for the B1 receptor (M. N. Perkins et al., Pain, 1993, 53, 191-197). Recently, a B2 receptor antagonist of non-peptide structure, SR 173657, has been described in Archiv Pharmacol., 1996, Suppl. 1, 354 (.4), R6.
According to the present invention, a novel family of compounds having affinity for the bradykinin receptors has now been found; these compounds are N-(arylsulphonyl)amino acid derivatives.
Among the N-(arylsulohonyl)amino acid derivatives, some are known and have various pharmacological activities. Thus, compounds with anti-thrombotic activity are described in the European, German and international patents or patent applications EP 558,961, EP 236,163, EP 236,164, DD 155,954, DE 4,115,468 and WO 92/16549. In this field of activity, NAPAP, derived from N-(naphthalenesulphonyl)-glycine of formula: 
is described in Pharmazie, 1987, 42 (5), 346. 
Furthermore, N-tosyl-xcex2-alanine derivatives of formula: in which a and b, together with the nitrogen atom to which they are attached, constitute a ring such as piperidine, pyrrolidine or morpholine, are described in Pharmazie, 1984, 39 (5), 315-317.
Similarly, N-(arylsulphonyl)proline derivatives have been cited as thrombin inhibitors in Pharmazie, 1986, 41 (4), 233-235 and Pharmazie, 1987, 42 (2), 114-116.
Moreover, patent application EP 614,911 describes compounds of formula: 
in which, in particular:
ArI is a naphthyl, a phenyl, a quinolyl or an isoquinolyl, which are optionally substituted;
ArII is a phenyl or a thienyl, which are optionally substituted;
RI, RII and Rxe2x80x2II are, independently of each other, H or (C1-C4) alkyl;
or RI is nothing and N is linked to ArII and optionally RI, and Rxe2x80x2II form a double bond;
or RI or RII is linked to ArII and is a (C1-C4) alkylene;
RIII and RIV, which may be identical or different, are H, (C1-C4) alkyl or form, together with the nitrogen atom to which they are attached, a (C5-C7) heterocycle;
Z1 is a (C1-C12)alkylene;
Q1 is methyl, amino, (C1-C4)alkoxycarbonylamino, (C1-C4) alkylamino, di(C1-C4)alkylamino, pyrrolidinyl, piperidino, morpholino, piperazinyl, (C1-C4)alkyl-4-piperazinyl, amidino, (C1-C4)alkylamidino, guanidino, (C1-C4)alkylguanidino, pyridyl, imidazolyl, pyrimidinyl, indolyl, hydroxyl, (C1-C4)alkoxy, (C2-C8)alkoxycarbonyl, amino(C1-C4)alkyl-N-(C1-C4)alkyl-amino, carbamoyl or phenyl, which is optionally substituted;
Q2 is H or (C1-C4)alkyl;
Q3 is H or (C1-C4)alkyl or Q1 and Q3 are linked to form a heterocycle and together are (C2-C3)alkylene when Z1 is nothing, in the form of pure enantiomers or mixtures thereof in any proportion; as well as the salts thereof with acids.
These compounds have affinity for the biological receptors of the neuropeptide Y.
According to the present invention, novel compounds have now been found which have, unexpectedly, affinity for the bradykinin receptors.
The subject of the present invention is the compounds of formula: 
in which:
R1 is a phenyl, a naphthyl, a tetrahydronaphthyl, a quinolyl or an isoquinolyl, the said rings being unsubstituted or substituted one or more times with R10;
R2 is a phenyl which is unsubstituted or substituted one or more times with R11, a phenyl(C1-C4)alkyl which is unsubstituted or substituted one or more times on the phenyl with R11, a naphthyl which is unsubstituted or substituted one or more times with R11, a cyclohexyl which is unsubstituted or substituted one or more times with R11;
or R2 and R9 are linked together and constitute a (C3-C5)alkylene which is unsubstituted or substituted with R12 or a (C2-C4)alkylene which is interrupted with an oxygen atom or a sulphur atom and is unsubstituted or substituted with R12;
or R2 and R9, together with the carbon atom and the nitrogen atom to which they are attached, constitute tetrahydroisoquinoline which is unsubstituted or substituted one or more times with a halogen, a hydroxyl, a (C1-C4)alkyl, a (C1-C4)alkoxy or a benzyloxy;
R3 is hydrogen or a hydroxyl;
R4 and R5 are each independently hydrogen or a (C1-C4) alkyl;
or R4 and R5, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from 1-pyrrolidinyl, 1-piperidyl, perhydro-1-azepinyl, 4-morpholinyl, 4-oxo-l-piperidyl, dihydro-l-pyrrolyl or dihydro-2-imidazolyl, the said heterocyclic radicals being unsubstituted or substituted one or more times with R13;
R6 is hydrogen and R6 can also be R8 when R7 is hydrogen;
R7 is hydrogen or a (C1-C4)alkyl;
R8 is hydrogen; a benzyl which is unsubstituted or substituted on the phenyl one or more times with R13; or a group ZR14;
or R7 and R8, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from 1-pyrrolidinyl, 1-piperidyl, 1-perhydro-1-azepinyl, 4-morpholinyl, tetrahydro-2-pyrimidinyl, 1-piperazinyl or 1-piperazinyl substituted in position 4 with a (C1-C4)alkyl or a benzyl;
or, when R7 is hydrogen, R6 and R8 are linked together to form a (C2-C4)alkylene which is unsubstituted or substituted one or more times with a (C1-C4) alkyl;
R9 is hydrogen, a (C1-C4)alkyl or a phenyl(C1-C4)alkyl which is unsubstituted or substituted on the phenyl one or more times with R11;
R10 is a halogen, a (C1-C4)alkyl, a (C1-C4)alkoxy, a hydroxyl, an amino, a (C1-C4)alkylamino or a di(C1-C4) alkylamino;
R11 is a halogen, a (C1-C4)alkyl, a trifluoromethyl, a phenyl, a hydroxyl, a (C1-C4)alkoxy or a benzyloxy;
or R11 is in the ortho position to the phenyl representing R2 and forms with R3 a methylene group or an ethylene group;
or R11 is in the ortho position to the phenyl representing R2 and forms with R9 a methylene group or an ethylene group;
R12 is a halogen, a (C1-C4)alkyl, a hydroxyl, a (C1-C4)alkoxy, a benzyloxy, an oxo, a phenyl, an acetyloxy or a trifluoroacetyloxy;
R13 is a (C1-C4)alkyl, a halogen or a hydroxyl;
R14 is a methyl, an amino, a (C1-C4)alkylamino, a di(C1-C4) alkylamino, a tri (C1-C4) alkylammonium, an amidino, a (C1-C4)alkylamidino, a guanidino, a (C1-C4)alkylguanidino, a hydroxyl, a (C1-C4)alkoxy, a (C1-C4)alkoxycarbonyl, a group xe2x80x94AlkN(R15)Alkxe2x80x2N(Rxe2x80x215)2, or a heterocyclic radical chosen from 1-pyrrolidinyl, 1-piperidyl, perhydro-1-azepinyl, pyridyl, imidazolyl, dihydroimidazolyl, imidazolidinyl, pyrimidinyl and indolyl;
R15 and Rxe2x80x215 are, independently of each other, hydrogen or a (C1-C4)alkyl;
R16 is hydrogen or a methyl, or R16 forms with R9 a methylene group;
R17 is hydrogen or a methyl;
Alk and Alkxe2x80x2 are, independently of each other, a (C1-C4)alkylene;
Z is a (C2-C12)alkylene or a (C1-C6)alkylene which is interrupted or substituted with a (C5-C7)cycloalkyl or with a phenyl;
C* is an asymmetric carbon atom; as well as the salts thereof with inorganic or organic acids.
The salts are generally prepared with pharmaceutically acceptable acids, but the salts of other acids which are useful for the purification or isolation of the compounds of formula (I) also form part of the invention. The pharmaceutically acceptable salts of the compounds of formula (I) are, for example, the hydrochloride, the hydrobromide, the sulphate, the methanesulphonate, the benzenesulphonate, the naphthalenesulphonate, the maleate, the fumarate, the citrate, the acetate, the gluconate, the dobesilate or the sultosilate.
The compounds of formula (I) comprise 2 (or possibly more) asymmetric carbon atoms and the 4 (or possibly more) pure enantiomers, as well as the mixture thereof in any proportion, are subjects of the invention.
The term halogen is understood to refer to chlorine, fluorine, bromine or iodine, chlorine and fluorine being preferred.
The terms, alkyl, alkylene and alkoxy are understood to refer, respectively, to a linear or branched alkyl radical, alkylene radical or alkoxy radical.
Those compounds of formula (I) are preferred in which:
R1 is a phenyl, a naphthyl, a tetrahydronaphthyl, a quinolyl or an isoquinolyl, the said rings being unsubstituted or substituted one or more times with R10;
R2 is a phenyl which is unsubstituted or substituted one or more times with R11, a phenyl(C1-C4)alkyl which is unsubstituted or substituted one or more times on the phenyl with R11, or a naphthyl which is unsubstituted or substituted one or more times with R11;
or R2 and R9 are linked together and constitute a (C3-C5)alkylene which is unsubstituted or substituted with R12 or a (C2-C4)alkylene which is interrupted with an oxygen atom or a sulphur atom and is unsubstituted or substituted with R12;
or R2 and R9 together with the carbon atom and the nitrogen atom to which they are attached, constitute tetrahydroisoquinoline which is unsubstituted or substituted one or more times with a halogen, a hydroxyl, a (C1-C4)alkyl, a (C1-C4)alkoxy or a benzyloxy;
R3 is hydrogen or a hydroxyl;
R4 and R5 are each independently hydrogen or a (C1-C4) alkyl;
or R4 and R5, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from 1-pyrrolidinyl, 1-piperidyl, perhydro-1-azepinyl, 4-morpholinyl or 4-oxo-1-piperidyl, the said heterocyclic radicals being unsubstituted or substituted with R13;
R6 is hydrogen, R6 can also be R8 when R7 is hydrogen;
R7 is hydrogen or a (C1-C4)alkyl;
R8 is hydrogen; a benzyl which is unsubstituted or substituted on the phenyl one or more times with R13; or a group ZR14;
or R7 and R8, together with the nitrogen atom to which they are attached, constitute a heterocyclic radical chosen from 1-pyrrolidinyl, 1-piperidyl, perhydro-1-azepinyl, 4-morpholinyl, 1-piperazinyl or 1-piperazinyl substituted in position 4 with a (C1-C4)alkyl or a benzyl;
or, when R7 is hydrogen, R6 and R8 are linked together to form a (C2-C4)alkylene which is unsubstituted or substituted one or more times with a (C1-C4) alkyl;
R9 is hydrogen, a (C1-C4)alkyl or a phenyl(C1-C4)alkyl which is unsubstituted or substituted on the phenyl one or more times with R11;
R10 is a halogen, a (C1-C4)alkyl, a (C1-C4)alkoxy, a hydroxyl, an amino, a (C1-C4)alkylamino or a di(C1-C4) alkylamino;
R11 is a halogen, a (C1-C4)alkyl, a hydroxyl, a (C1-C4)alkoxy or a benzyloxy;
R12 is a halogen, a (C1-C4)alkyl, a hydroxyl, a (C1-C4)alkoxy, a benzyloxy, an oxo or a phenyl;
R13 is a (C1-C4)alkyl, a halogen or a hydroxyl;
R14 is a methyl, an amino, a (C1-C4)alkylamino, a di(C1-C4)alkylamino, a tri(C1-C4)alkylammonium, an amidino, a (C1-C4)alkylamidino, a guanidino, a (C1-C4)alkylguanidino, a hydroxyl, a (C1-C4)alkoxy, a (C1-C4)alkoxycarbonyl, a group-AlkN(R15)Alkxe2x80x2N(Rxe2x80x215)2, or a heterocyclic radical chosen from. 1-pyrrolidinyl, 1-piperidyl, perhydro-1-azepinyl, pyridyl, imidazolyl, dihydroimidazolyl, imidazolidinyl, pyrimidinyl and indolyl;
R15 and Rxe2x80x215 are, independently of each other, hydrogen or a (C1-C4)alkyl;
R16 is hydrogen;
R17 is hydrogen;
Alk and Alkxe2x80x2 are, independently of each other, a (C1-C4) alkylene;
Z is a (C2-C12)alkylene or a (C1-C6)alkylene which is interrupted or substituted with a (C5-C7)cycloalkyl or with a phenyl; as well as the salts thereof with inorganic or organic acids.
Certain values for the substituents are preferred. Thus, the preferred compounds of formula (I) are those which satisfy at least one of the following conditions:
axe2x80x94R1 is a naphthyl, a quinolyl or a trichlorophenyl; R2, R3, R4, R5, R6, R7, R8, R9, R16 and R17 being as defined above for formula I;
bxe2x80x94R2 is a phenyl which is unsubstituted or substituted with R11; R1, R3, R4, R5, R6, R7, R8, R9, R16 and R17 being as defined above for formula I;
cxe2x80x94NR4R5 is a 1-pyrrolidinyl group; R1, R2, R3, R6, R7, R8, R9, R16 and R17 being as defined above for formula I;
dxe2x80x94C(NR6)NR7R8 is a 4,5-dihydro-2-imidazolyl; R1, R2, R3, R4, R5, R9, R16 and R17 being as defined above for formula I;
exe2x80x94R3xe2x95x90R9xe2x95x90R16xe2x95x90R17xe2x95x90H; R1, R2, R4, R5, R6, R7 and R8 being as defined above for formula I; and the salts thereof with inorganic or organic acids.
According to the invention, the preferred compounds are those of formula: 
in which:
R2a is a phenyl which is unsubstituted or substituted in a meta or para position with R11; a 1-naphthyl or a 2-napohthyl;
R1, R6, R7, R8 and R11 are as de fined above for (I); and the salts thereof with inorganic or organic acids.
Most particularly, the preferred compounds are those of formula: 
in which:
R1a is a 1-naphthyl, a 2-naphthyl, a 2,4,6-trichlorophenyl or a 2-quinolyl;
R2a is as defined above for (Ia);
and the salts thereof with inorganic or organic acids.
More particularly, the preferred compounds are those of formula (Ixe2x80x2a) in which R2a is a phenyl which is unsubstituted or substituted in a meta or para position with R11.
Most particularly, the preferred compounds are those of formula (I), (Ia) or (Ixe2x80x2a) having (R,R) isomerism on-the C*-labelled carbon atoms.
The following abbreviations are used in the description and in the claims:
Me: methyl
Et: ethyl
iPr: isopropyl
nBuOH: n-butanol
iPrOH: isopropanol
EtOH: ethanol
MeOH: methanol
Et2O: ether: diethyl ether
DMF: dimethylformamide
DCM: dichloromethane
THF: tetrahydrofuran
AcOH: acetic acid
EtOAc: ethyl acetate
DIPEA: diisopropylethylamine
DMAP 4-dimethylaminopyridine
DCC: 1,3-dicyclohexylcarbodiimide
DCU: dicyclohexylurea
NSuOH: N-hydroxysuccinimide
NSu: succinimido
NBS: N-bromosuccinimide
Fmoc fluorenylmethoxycarbonyl
Boc: tert-butoxycarbonyl
(Boc)2O: di-tert-butyl dicarbonate
Et3N: triethylamine
Bn: benzyl
Pd/C palladium-on-charcoal
Sephadex(copyright) LH 20: sold by Pharmacia
Sephadex(copyright) G 25: sold by Pharmacia
Alcalase(copyright): Carlsberg subtilisin sold by Novo (Denmark)
Penicillin amidase:penicillin amidohydrolase, sold by Sigma
BOP: benzotriazol-1-yloxytris(dimethylamino)-phosphonium hexafluorophosphate
K2CO3: potassium carbonate
K2SO4: potassium sulphate
KHSO4: potassium hydrogen sulphate
KHSO4/K2SO4: solution of 16.66 g of KHSO4 and 32.32 g of K2SO4 in 1 l of water
NaCl: sodium chloride
Na2SO4: sodium sulphate
MgSO4: magnesium sulphate
NaOH: sodium hydroxide
NH4OH: aqueous ammonia
HCl: hydrochloric acid
TFA: trifluoroacetic acid hydrochloric ether: saturated solution of hydrogen chloride gas in diethyl ether
mpa.s: milliPascal/second
m.p.: melting point
RT: room temperature
NMR: nuclear magnetic resonance
DMSO dimethyl sulphoxide
xcex4: chemical shift
s: singlet; bs: broad singlet; ds: doubled singlet; d: doublet; dd: doubled doublet; t: triplet; bt: broad triplet; q: quartet; quint: quintet; mt: multiplet; m: unresolved multiplet
The subject of the present invention is also the process for the preparation of the compounds of formula (I) and the salts thereof. This process, referred to as process 1, is characterized in that:
a1) a compound of formula: 
xe2x80x83in which R1, R2, R3, R4, R5, R9, R16, R17 and C* have the definitions given above for (I), in the form of a pure enantiomer or a mixture of isomers in any proportion, is treated with an alcohol of formula Rxe2x80x94OH in which R is a (C1-C4)alkyl, in acidic medium, in order to form an intermediate imidate which is reacted with an amine of formula HNR7R8 (III) or a diamine of formula H2NR6R8NH2 (IV) in which R6, R7 and R8 have the definitions given above for (I);
b1) the compound of formula (I) thus obtained is isolated in base form or salt form,
c1) where appropriate, another salt of the compound of formula (I) is prepared.
Many processes for the synthesis of amidines are described in the book xe2x80x9cThe chemistry of amidines and imidatesxe2x80x9d, D. G. Neilson, Ed. Saul PataÏ, Wiley and Sons, 1975, 389-394. The preparation of certain amidines is described precisely in patent application EP 614,911 A.
The formation of the imidate is preferably carried out in a strong acid medium, whereas the imido ester in free base form or in salt form is reacted with the amine (III) or the diamine (IV) in an inert polar solvent, for example an alcohol, at a temperature of between 0xc2x0 C. and the ref lux temperature of the solvent.
The intermediate imidate is reacted with an amine whose formula depends on that of the compound (I) which it is desired to obtain. In order to prepare a compound of formula (I) in which R6xe2x95x90H, an amine HNR7R8 is reacted; in order to prepare a compound of formula (I) in which R6=R8 and R7=H, two moles of an amine of formula H2NR8 are reacted per mole of imidate; in order to prepare a compound of formula (I) in which R7 is hydrogen and R6 and R8 are linked together to form a (C2-C4)alkylene which is unsubstituted or substituted one or more times with an alkyl, a diamine of formula H2NR6R8NH2 is reacted.
Most of the amines (III) and of the diamines (IV) are known and the novel products can be prepared by applying principles and methods that are well known to those skilled in the art. For example, for the derivatives in which R14 is an imidazolyl, reference will be made to U.S. Pat. No. 3,881,016 and to the publication Synith. Communic. 1987, 17 (21), 223-227.
The compounds of formula (I) in which R14 is NH2 or alkylamino can be prepared by hydrolysis of the compounds of formula (I) in which R14 contains a t-butoxycarbonylamino group, which is in turn obtained according to Synth. Commun. 1990, 20 (16), 2559-2564.
The compounds of formula (I) in which R14 is a substituted or unsubstituted guanidino group can be prepared by the action on the compound of formula (I), in which R14xe2x95x90NH2, of a compound of formula: 
in which T is H or (C1-C4)alkyl and Y is a nucleofugal group, such as SO3H, for example, aminoiminomethanesulphonic acid (under the conditions described in Tetrahedron Letters, 1988, 3183-3186) or N-methylaminoiminomethanesulphonic acid (obtained according to the process described in J. Org. Chem., 1986, 51(10), 1882).
The action of an amine (III) of formula H2NR8 in excess on the imidate resulting from the reaction of ROH with a compound of formula (II) leads to the formation of a mixture of two compounds of formula (I): for one R6=R7=H and for the other R6=R8 and R7=H.
The compounds of formula (I) in which R6 and R8 together form a (C2-C4)alkylene which is unsubstituted or substituted one or more times with a (C1-C4)alkyl can be prepared in a manner which is known per se, by the action of a diamine H2Nxe2x80x94R6R8xe2x80x94NH2 on the imido ester or optionally by the action of the same diamine, one of the functions of which is protected by a labile group (such as Boc or Fmoc for example) which will be removed before cyclization.
The compounds of formula (I) in which R14 is a dihydroimidazole can be prepared by the action of an alcohol in acidic medium on a compound of formula: 
in order to form an intermediate imidate, which is reacted with an appropriate amine according to the usual methods.
The nitriles of formula (II) are prepared using the standard methods of peptide chemistry, for example those described in The Peptides Ed. E. Gross and J. Meienhofer, Academic Press, 1979, 1, 65-104. Known methods make it possible to carry out peptide couplings without racemization of the carbon atoms of each constituent amino acid; furthermore, the xcex2-substituted xcex2-alanines for which the chiral carbon is not adjacent to the carboxyl group are reputed as not suffering racemization. (Ann. Rev. Biochem., 1986, 55, 855-878). Moreover, patent application EP 236,163 describes processes which allow the chirality of each amino acid to be conserved.
In general, the coupling reactions between the 2 amino acids take place at temperatures of between 0xc2x0 C. and 40xc2x0 C. in an inert solvent such as dichloromethane, acetonitrile, tetrahydrofuran or dimethylformamide, in the presence of a coupling agent and of at least one equivalent of a tertiary amine such as triethylamine, N-ethylmorpholine or diisopropylethylamine.
Thus, the preparation of a nitrile of formula (II) can be carried out according to one of the synthetic routes below. 
In order to prepare a compound of formula (V), which is useful in route 1, the radical R1SO2 is introduced in a conventional manner by the action of a sulphonyl halide of formula: R1SO2Hal in which R1 is as defined above for (I) and Hal is a halogen, preferably chlorine, on a compound of formula: 
in which R2, R3 and R9 have the meanings given above for (I) and Rxe2x80x2 is hydrogen or a (C1-C4)alkyl.
A compound of formula (V) in which R3 is hydrogen can also be prepared in 2 steps: firstly, a compound of formula: 
in which Y is R1SO2 or a protecting group such as Boc or Fmoc, after which the carbon chain is extended by one atom using known methods, then, if necessary, the protecting group is removed and a sulphonyl halide of formula R1SO2Hal is reacted and, lastly, the group Rxe2x80x2 is removed, if it is other than H.
This procedure is suitable, for example, when R2 and R9 are linked together and constitute a (C3-C5)-alkylene which is unsubstituted or substituted with R12 or a (C2-C4)-alkylene which is interrupted by an oxygen atom or a sulphur atom which is unsubstituted or substituted one or more times with R12.
The sulphonyl halides are known or are prepared by known methods.
The compounds of formula (VI) are prepared by the action of an amine HNR4R5 on an amino acid of formula: 
in which the amine is protected, for example by a Boc or Fmoc group, followed by the removal of the protecting group.
In the reaction sequence of route 2, the amine is deprotected in acidic medium (TFA) and the radical R1SO2 is introduced in a conventional manner by the action of a sulphonyl halide of formula: R1SO2Hal in which R1 is as defined above for (I) and Hal is a halogen, preferably chlorine.
In route 1, as in route 2, the group R1SO2 is introduced in the presence of a base, optionally in a two-phase medium, in the presence of a phase-transfer catalyst.
A substituent R9 can be introduced into a compound of formula (II) in which R9=H by known methods, for example by the action of a halide of formula R9Hal, in which Hal is a halogen atom, for example chlorine.
The compounds of formula (II) in which R9 and R16 together form a methylene group are prepared by the action of para-formaldehyde on compounds of formula (II) in which R9=R16=H.
The compounds of formula (II) are novel and constitute a further aspect of the present invention.
Certain compounds of formula (V), which are toluenesulphonamide or phenylsulphonamide derivatives, have been described in the following publications: Tetrahedron, 1993, 49 (48), 11329-11340; Centralblatt, 1929, II, 1398; J. Org. Chem., 1978, 43(23), 4438-4441; J. Org. Chem., 1966, 31(7), 2385-2386.
Thus, the compounds of formula: 
in which R1, R2, R3, R9 and C* are as defined for (I); it being understood that:
when R1 is phenyl or p-tolyl and R3 is hydrogen, then R2 and R9, together with the carbon and nitrogen atoms to which they are attached, are not pyrrolidinyl or 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolyl, and
when R1 is p-tolyl and R9 is hydrogen, then R2 is not an unsubstituted phenyl; are novel and form part of the invention.
In order to prepare a compound of formula (I) in which R9 and R11, together form a methylene or ethylene group, a beta-amino acid-of formula (XIII) 
in which R9 and R11 form a methylene or ethylene group, is prepared using known methods, for example the one described in J. Org. Chem., 1987, 52, 616-622.
In order to prepare a beta-amino acid of formula (XIII) in which R3 and R11 together form a methylene or ethylene group, known methods are used. Thus, methyl 1-aminoindane-2-carboxylate is prepared in 3 steps from 1-indanone: according to J. Med. Chem., 1970, 650, the action of methyl carbonate in the presence of sodium hydride makes it possible to obtain methyl (1-oxo)indane-2-carboxylate, then, according to J. Heterocycl. Chem., 1974, 11, 982, methyl 1-hydroxyiminoindan-2-carboxylate is prepared and, lastly, the hydroxylamine is reduced to amine in the presence of a catalyst.
1-Amino-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid can be prepared according to the method described in J. Chromatogr., A 1994, 676, 297-302. Alternatively, according to another process, when the amidine group C(xe2x95x90NR6)NR7R8 contains no function liable to react in a subsequent step under the peptide coupling conditions, an amino acid derivative containing the amidine group can be prepared from the corresponding derivative containing a cyano group, and the couplings required co obtain a compound according to the invention can then be carried out.
Thus, according to a further aspect, the subject of the present invention is another process for the preparation of a compound of formula (I), which is referred to as process 2, characterized in that:
a2) a compound of formula: 
xe2x80x83in which X is hydrogen or a Boc group and R4, R5 and C* are as defined for (I), in the form of a pure enantiomer or a mixture of isomers in any proportion, is treated with an alcohol of formula Rxe2x80x94OH in which R is a (C1-C4)alkyl, in acidic medium, in order to form an intermediate imidate which is reacted with an amine of formula HNR7R8 (III) or a diamine of formula H2NR6R8NH2 (IV) in which R6, R7 and R8 have the definitions given above for (I):
b2) the compound thus obtained, of formula: 
xe2x80x83is coupled
either with a compound of formula: 
xe2x80x83in which R2, R3 and R9 are as defined for (I) and Pr is a protecting group, for example Boc or Fmoc, then, after deprotection of the amine in acidic medium, a sulphonyl halide of formula R1SO2Hal in which R1 is as defined for (I) and Hal is a halogen, for example chlorine, is reacted;
or with a compound of formula: 
xe2x80x83in which R1, R2, R3 and R9 are as defined for (I):
c2) the compound of formula (I) thus obtained is isolated in base form or in salt form;
d2) where appropriate, another salt of the compound of formula (I) is prepared.
The compounds of formulae (VI) and (XI) in optically pure form can be obtained from an ester, for example the racemic ethyl ester of 4-cyanophenylalanine, according to the reaction scheme described below: 
The racemic ethyl ester of 4-cyanophenylalanine is described in patent application EP 614,911 A. The amine function of this compound is protected in a conventional manner, by the action of (Boc)2O in the presence of triethylamine. The action of an enzyme, Alcalase(copyright), on the compound 4 thus obtained makes it possible to selectively hydrolyse the ester function of the amino acid of (L) configuration and thus to isolate each of the compounds 5 and 6 in optically pure form (Synthesis, 1983, 1041-1043).
The compound of (L) configuration is isolated in acid form: (L) 6. The compound of (D) configuration is isolated in the form of an ethyl ester (D) 5; this compound is hydrolysed with sodium hydroxide in order to obtain the acid form: (D) 6. Each of these 2 compounds of formula 6 is then treated with N-hydroxysuccinimide in an inert solvent such as DMF or dioxane, in the presence of a coupling agent such as DCC in order to obtain a compound of formula 7. The action of an amine HNR4R5, followed by the action of trifluoroacetic acid, makes it possible to prepare the compounds of formulae (L) (VI) and (D) (VI); the conventional reactions described above are then carried out in order to obtain the desired amidines of formulae (L) (XI) and (D) (XI).
The beta-amino acids of formula XIII: 
or the corresponding aliphatic esters are known or can be prepared by various methods, for example according to J. Am. Chem., 1936, 58, 299. One specific way of preparing the beta-amino acids consists in carrying out a chain extension starting with an alpha-amino acid, according to Tetrahedron, 1994, 50, 9457-9470 or according to J. Chem. Soc., Perkin Transact. II, 1977, 370.
More specifically, the preparation of certain beta-amino acids of formula (XIV) H2Nxe2x80x94CH(R2)xe2x80x94CH2xe2x80x94COOH is described in the following publications or patents.
The compounds (I) in which R2 and R9 are linked together and constitute a C3-C5 alkylene which is unsubstituted or substituted with R12 are prepared from compounds of formula (XIII) which are known or are prepared by known methods.
In order to obtain optically pure compounds of formula (XIII) or (XIV), it is possible, for example, to use a menthol ester according to the technique described in Tetrahedron Lett., 1988, 29, 6465-6466; a quinine or quinidine salt can also be used, according to Chem. Ber., 1910, 43, 2020, or alternatively the phenylacetamido derivative of the compound of formula (XIV) in racemic form can be used for an enzymatic resolution with a penicillin amylase (Synlett, 1993, 339). Enantioselective syntheses can also be carried out: Tetrahedron, 1994, 50, 9517; Aldrichimica, Acta, 1994, 27(1), 3.
In order to prepare an alpha-hydroxy-beta-amino acid, the method described in Bull. Soc. Chim., France, 1940, 7, 593-603 can be used.
The affinity of the compounds-according to the invention for the bradykinin B1 receptors was measured on suspensions of MRC5 cell membranes using a technique similar to that described by K. H. Schneck et al., in Eur. J. Pharmacol., 1994, 266, 227-282. In this test, the affinity of [des-Arg9] bradykinin is between 10xe2x88x926M and 10xe2x88x927M, that of [des-Arg10] kallidin is 2xc3x9710xe2x88x929M; and the compounds of the invention have an affinity ranging down to 10xe2x88x9210M.
The affinity of the compounds according to the invention for the bradykinin B2 receptors was measured on suspensions of MRC5 cell membranes according to a technique similar to that described by D. G. Sawutz et al., in Eur. J. Pharmacol., 1992, 227, 309-315. In that test, the affinity of bradykinin is close to 10xe2x88x929M and that of the compounds of the invention varies around 10xe2x88x926M or 10xe2x88x927M.
The toxicity of the compounds according to the invention is compatible with their therapeutic use.
The compounds according to the invention may be useful for the treatment or prevention of many pathologies, in particular inflammation pathologies and persistent or chronic inflammatory diseases (Drug News and Perspectives, 1994, 10(7), 603-611). By way of example, mention may be made of:
neurogenic inflammation, pain (Brit. J. Pharmacol., 1993, 110, 193-198), septic shock, asthma, rheumatoid arthritis, inflammatory diseases of the joints, burns (Pain, 1993, 53, 191-197), wounds, diseases of the respiratory tracts, for example rhinitis of viral or allergic origin, systematic inflammatory response syndrome, oedema (Brit. J. Pharmacol., 1995, 114, 1005-1013), angiogenesis (Brit. J. Pharmacol., 1993, 109, 14-17), type-I infectious diabetes (Abst. 14th Intern. Symp. on Kinins, C49, Denver Colorado, Sep. 10-15, 1995), ventricular hypertrophy associated with diabetes, pulmonary fibrosis and systemic progressive sclerosis, enterocolitis, and more generally any bradykinin-dependent pathology.
The compounds according to the invention are generally administered in dosage units.
The invention also relates to pharmaceutical compositions comprising, as active principle, one of the enantiomers of the compounds of formula (I), a mixture thereof or salts thereof with a pharmaceutically acceptable acid, as well as to an excipient which is suitable for oral, injectable, topical or transdermal administration. The daily doses depend on the pathology to be treated and on the patient.
The subject of the present invention is also pharmaceutical compositions containing an effective dose of a compound according to the invention or of a pharmaceutically acceptable salt and suitable excipients.
The said excipients are chosen depending on the pharmaceutical form and the desired mode of administration.
In the pharmaceutical compositions of the present invention for oral, sublingual, subcutaneous, intramuscular, intravenous, topical, intratracheal, intranasal, transdermal or rectal administration, the active principles of formula (I) above, or the possible salts thereof, can be administered in unit forms of administration, as a mixture with standard pharmaceutical supports, to animals and to human beings for the prophylaxis or treatment of the above disorders or diseases. The appropriate unit forms of administration comprise oral forms such as tablets, gelatin capsules, powders, granules or oral solutions or suspensions, sublingual, buccal, intratracheal or intranasal administration forms, subcutaneous, intramuscular or intravenous administration forms and rectal administration forms. For topical application, the compounds according to the invention can be used in creams, ointments, gels or lotions.
In order to obtain the desired prophylactic or therapeutic effect, the dose of active principle can range between 0.01 and 50 mg per kg of body weight and per day.
Each unit dose can contain from 0.5 to 1000 mg, preferably from 1 to 500 mg, of active ingredients in combination with a pharmaceutical support. This unit dose can be administered 1 to 5 times a day so as to administer a daily dose of from 0.5 to 5000 mg, preferably from 1 to 2500 mg.
When a solid composition is prepared in the form of tablets, the main active ingredient is mixed with a pharmaceutical vehicle such as gelatin, starch, lactose, magnesium stearate, talc, gum arabic or the like. The tablets can be coated with sucrose, with a cellulose derivative or with other suitable materials or alternatively they can be treated such that they have sustained or delayed activity and such that they release a predetermined amount of active principle continuously.
A preparation as gelatin capsules can be obtained by mixing the active ingredient with a diluent such as a glycol or a glycol ester and by pouring the mixture obtained into soft or hard gelatin capsules.
A preparation in syrup or elixir form or for administration in the form of drops can contain the active ingredient together with a sweetener, preferably a calorie-free sweetener, methylparaben and propylparaben as antiseptic, as well as a flavouring agent and a suitable dye.
The water-dispersible powders or granules can contain the active ingredient as a mixture with dispersing agents; wetting agents or suspension agents, such as polyvinylpyrrolidone, as well as with sweeteners or flavour enhancers.
For rectal administration, use is made of suppositories which are prepared with binders which melt at the rectal temperature, for example cocoa butter or polyethylene glycols.
Aqueous suspensions, isotonic saline solutions or sterile and injectable solutions which contain pharmacologically compatible dispersing agents and/or wetting agents, for example propylene glycol or butylene glycol, are used for parenteral administration.
Creams, ointments, lotions or gels, for example, can be used for local administration.
Patches in multilaminar or reservoir form in which the active principle may be dissolved can be used for transdermal administration.
The active principle can also be formulated in the form of microcapsules, optionally with one or more supports or additives.
The compositions of the present invention can contain, along with the products of formula (I) above or one of the pharmaceutically acceptable salts, other active principles which can be used in the treatment of the disorders or diseases mentioned above.
The preparations and the examples below illustrate the invention. Except where otherwise mentioned, the compounds are obtained in the form of a mixture of diastereoisomers.
The nuclear magnetic resonance (NMR) spectra are recorded at 200 MHz in deuterated DMSO optionally containing TFA, using tetramethylsilane as reference. The chemical shifts are indicated in ppm.
The mass spectra indicate the value MH+.
Preparation 1.1
4.06 g of 2-[N-(BOc)amino]-3-(4-cyanophenyl)-propionic acid are mixed with 1.15 ml of pyrrolidine and 7.5 g of BOP in 20 ml of DMF; the mixture is left stirring for 2 hours at RT while maintaining at pH=7 by addition of Et3N. After evaporating to dryness, the residue is chromatographed on silica, eluting with a chloroform/methanol mixture (9/0.5; v/v). After evaporating off the solvents, the solid obtained is treated with 20 ml of TFA in 20 ml of DCM for 30 minutes at RT. The solvents are evaporated off and the residue is taken up in ether and then dried in order to obtain 3.95 g of the expected product.
Preparation 1.2
1-[2-Amino-3-(4-(3,4-dihydroimidazol-2-yl)phenyl)-propionyl]pyrrolidine dihydrochloride
18 g of 1-[2-((N-Boc)amino)-3-(4-cyanophenyl)-propionyl]pyrrolidine are dissolved in 90 ml of DCM, 90 ml of TFA are added and the mixture is left stirring for 40 minutes at RT. After evaporating to dryness, the residue is taken up in DCM and then evaporated (twice). The residue is then taken up in 300 ml of HCl-saturated anhydrous ethanol at 0xc2x0 C. and the mixture is left for 18 hours at +4xc2x0 C. The medium is evaporated to dryness, taken up in ethanol, evaporated again and then taken up again in DCM and evaporated (twice). 23 g of intermediate imidate are obtained. The product obtained is dissolved in 1 liter of anhydrous ethanol and 4.41 g of ethylenediamine in 50 ml of anhydrous ethanol are added over 30 minutes. After stirring for 48 hours at RT, the medium is concentrated and then acidified to pH=2 by addition of a saturated solution of HCl in methanol. The mixture is drained, evaporated to dryness and then taken up in ether, drained and dried to give 17.4 g of the expected product.
NMR (DMSO+TFA): 1.50-1.80: m: 4H; 2.50-3.60: m: 6H; 4.00: s: 4H; 4.35: bs: 1H; 7.50: d: 2H; 8.15: d: 2H; 8.60: bs: 3H; 11.10: s: 2H.
Preparation 1.3
1-[2-Amino-3-(4-(N1-[3-(dimethylamino)propyl]amidino)-phenyl)propionyl]pyrrolidine tris(trifluoroacetate)
A) 1-[2-Amino-3-(4-(N1-[3-(dimethylamino)propyl]-amidino)phenyl)propionyl]pyrrolidine trihydrochloride
809 mg of 1-[2-amino-3-(4-cyanophenyl)-propionyl]pyrrolidine trifluoroacetate are dissolved in 50 ml of hydrochloric acid-saturated methanol at 0xc2x0 C. and the mixture is left overnight in a refrigerator. After evaporating to dryness, the imidate formed is taken up in toluene, the mixture is then evaporated and the residue is dried under vacuum over potassium hydroxide. The product obtained is dissolved in 75 ml of anhydrous methanol and 570 xcexcl of N-(dimethyl)-propane-1,3-diamine dissolved in 15 ml of anhydrous methanol are added slowly. After stirring for 3 hours at RT, the mixture is evaporated to dryness and the residue is then dissolved in 30 ml of methanol, adding 5 ml of 4N HCl in dioxane, and is evaporated to dryness.
B) 1-[2-(N-Boc)amino-3-(4-(N1-[3-(dimethylamino)-propyl]amidino)phenyl)propionyl]pyrrolidine dihydrochloride
The crude product obtained in the above step is dissolved in 10 ml of dioxane and 10 ml of water. Triethylamine is added to reach pH=8.3, followed by 600 mg of (Boc)2O and the mixture is left stirring at RT for 15 hours. The medium is diluted with water, washed twice with ether, acidified to pH=1.5 by addition of 1N HCl and then washed with DCM. This mixture is brought to pH=7 by addition of 1N sodium hydroxide and is evaporated to dryness. The residue is taken up in DCM, the insoluble material is filtered off and the filtrate is then purified by chromatography on silica, eluting with a chloroform/methanol mixture (85/15 to 80/20; v/v). 560 mg of the expected product are obtained.
C) 1-[2-Amino-3-(4-(N1-[3-(dimethylamino)propyl]-amidino)phenyl)propionyl]pyrrolidine tris(trifluoroacetate)
550 mg of the compound of step B are mixed with 15 ml of DCM and 15 ml of TFA and the mixture is left stirring for 45 minutes at RT. After evaporating to dryness, the residue is dissolved in isopropanol, evaporated to dryness again and taken up twice in ether. The product is isolated by decanting and then dried under vacuum in the presence of potassium hydroxide. 380 mg of the expected compound are obtained.
Preparation 1.4
1-[2-Amino-3-(4-cyanophenyl)propionyl]-2,5-dimethyl-2,5-dihydropyrrole trifluoroacetate
A) 1-[2-(N-Boc)amino-3-(4-cyanophenyl)propionyl]-2,5-dimethyl-2,5-dihydropyrrole
2.1 g of 2-[(N-Boc)amino]-3-(4-cyanophenyl)-propionic acid are mixed with 0.715 g of 2,5-dimethyl-2,5-dihydropyrrole in 10 ml of DMF, 3.9 g of BOP are added and the pH is adjusted to 7 by addition of Et3N. After stirring for 18 hours at RT, the mixture is evaporated to dryness and is then taken up in EtOAc, washed with NaHCO3 solution, with KHSO4/K2SO4 and with saturated NaCl solution. The resulting solution is dried over Na2SO4 and then evaporated. The residue is taken up in an ether/hexane mixture and then dried over Na2SO4. 1.4 g of the expected compound are obtained.
NMR: (DMSQ+TFA) 1.15-1.25: m: 6H; 1.30: s: 9H; 2.9-3.1: m: 2H; 4.3-4.6: m: H; 4.6-4.75: m: 1H; 4.9-5.1: m: 1H; 5.75-5.9: m: 2H; 7.5: d: 2H; 7.9: d: 2H.
B) 1-[2-Amino-3-(4-cyanophenyl)propionyl]-2,5-dimethyl-2,5-dihydropyrrole trifluoroacetate
The compound of the above step is dissolved in 5 ml of DCM, 5 ml of TFA are added and the mixture is left stirring for 40 minutes at RT. It is evaporated to dryness and the residue is taken up in DCM and evaporated (3 times) and is then taken up in an ether/hexane mixture. The product is drained and then dried over Na2SO4 in order to obtain 1.5 g of the expected product.
Working as in Preparation 1.4, step A above, the compounds described in the table below are prepared:
Preparation 1.8
1-[2-N-Methylamino-3-(4-cyanophenyl)propionyl]-pyrrolidine trifluoroacetate
A) 2-(N-Boc-N-methyl)amino-3-(4-cyanophenyl)propionic acid
1.16 g of 2-[N-Boc-amino]-3-(4-cyanophenyl)-propionic acid are dissolved in 20 ml of THF and 2 ml of methyl iodide are added at 0xc2x0 C., followed by portionwise addition of 360 mg of sodium hydride at 80% in oil. The mixture is left stirring overnight at RT. The reaction medium is diluted with EtOAc and then water is added and the pH is brought to 2.5 with 1N HCl. The organic phase is separated out after settling has taken place, then washed with water, with saturated NaCl solution and then dried over Na2SO4 and evaporated. The residue is taken up in an Et2O/hexane mixture (1/1; v/v). The powder formed is filtered off and dried to give 1.11 g of the expected compound.
NMR (DMSO+TFA): 1.20: ds: 9H; 2.55: ds: 3H; 2.90-3.25: m: 2H; 4.50-4.80: m: 1H; 7.30-7.70: m: 4H.
B) 1-[2-(N-Boc-N-methyl)amino-3-(4-cyanophenyl)-propionyl]pyrrolidine
1.10 g of the compound of the above step, 0.35 ml of pyrrolidine and 1.78 g of BOP are mixed with stirring in 15 ml of DMF and the pH is adjusted to 6 by addition of DIPEA. After stirring for 2 and a half hours, the mixture is extracted with EtOAc and the organic phase is then washed with 0.25N NaOH, 0.25N HCl, H2O and then with saturated NaCl solution. The thick wax formed sets to a solid after a few days at +40xc2x0 C. 1.25 g of the expected compound are obtained.
NMR (DMSO+TFA): 1.10: ds: 9H; 1.60-1.85: m: 4H; 2,60: ds: 3H; 2.75-3.40: m: 6H; 4.80-5.10: m: 1H; 7.25-7.70: m: 4H.
C) 1-[2-N-Methylamino-3-(4-cyanophenyl)propionyl]-pyrrolidine trifluoroacetate.
0.72 g of the compound of the above step is placed in 12 ml of TFA and 12 ml of DCM. After stirring for 40 minutes at RT, the reaction medium is concentrated under vacuum and then evaporated with DCM. 0.75 g of the expected compound is obtained in the form of a thick-wax.
Preparation 1.9
N,N-Diethyl-[2-amino-3-(4-(3,4-dihydroimidazol-2-yl)-phenyl)]propionamide dihydrochloride
N,N-Diethyl-[2-(N-Boc)amino-3-(4-cyanophenyl)]-propionamide is prepared by working according to the procedure described in Preparation 1.4, step A. The expected product is then obtained according to the procedure described in Preparation 1.2.
Preparation 1.10
Ethyl ester of 2-(N-Boc)amino-3-(4-cyanophenyl)-propionic acid
26 g of Boc2O dissolved in 100 ml of DCM are gradually added to a solution of 25.5 g of the ethyl ester hydrochloride of 2-amino-3-(4-cyanophenyl)-propionic acid and 13.9 ml of Et3N in 400 ml of DCM. After stirring for 6 hours at RT, the reaction medium is washed with KHSO4/K2SO4 solution, with saturated NaHCO3 solution and with saturated NaCl solution. After drying over Na2SO4 and evaporation of the DCM, the residue is triturated from heptane to give 29 g of white powder.
Preparation 1.11
Ethyl ester of (R)-2-(N-Boc)amino-3-(4-cyanophenyl)-propionic acid: compound B and (S)-2-(N-Boc)amino-3-(4-cyanophenyl)propionic acid: compound A
A mixture of 24 g of the product obtained above and 8.4 g of NaHCO3 in 900 ml of EtOAc and 500 ml of H20 is treated with 2 ml of Alcalase(copyright) for 24 hours at RT. The 2 phases are separated out after settling has taken place; the EtOAc phase is rewashed with 100 ml of 10% NaHCO3 solution which is added to the first aqueous phase and the aqueous phase is rewashed with 100 ml of EtOAc added to the first EtOAc phase. The EtOAc phase thus obtained is dried over Na2SO4 and then evaporated to dryness; 12.45 g of compound B are obtained.
xcex1D25=+8.8xc2x0 (c=1; MeOH)
The aqueous phase is taken up in EtOAc and brought to pH=2:5 with 6N HCl. EtOAc is separated out after settling has taken place and rewashed with KHSO4/K2SO4 solution, with saturated NaCl solution, dried over Na2SO4 and evaporated to dryness, and 10.1 g of compound A are obtained.
xcex1D25=+8.80xc2x0 (c=1; MeOH)
Preparation 1.12
1-[2-Amino-3-(4-cyanophenyl)propionyl]pyrrolidine trifluoroacetate, (S) isomer
A) 2,5-Dioxo-1-pyrrolidinyl ester of 2-(N-Boc)amino-3-(4-cyanophenyl)propionic acid, (S) isomer
99.85 g of 2-(N-Boc)amino-3-(4-cyanophenyl)-propionic acid, (S) isomer, and 4.14 g of NSuOH are dissolved in 100 ml of dioxane and 8.5 g of DCC dissolved in 30 ml of dioxane are added slowly at RT, after which the mixture is stirred for 8 hours at RT. The DCU is filtered off and washed with acetone. After evaporating the filtrate to dryness, the residue is dissolved in acetone and then left overnight at RT. The remaining DCU which has precipitated is removed and the filtrate is then evaporated to dryness, triturated from Et2O and then drained, washed with Et2O and dried. 11.5 g of the expected compound are obtained,
xcex1D25=xe2x88x9229.7xc2x0 (c=1, MeOH)
B) 1-[2-(N-Boc)amino-3-(4-cyanophenyl)propionyl]-pyrrolidine, (S) isomer
11 g of the compound of the above step are placed in 150 ml of acetonitrile and 20 ml of DMF and 2.5 ml of pyrrolidine in 30 ml of acetonitrile are added over 10 minutes. The mixture is left stirring for 2 hours at RT and is then left overnight at RT. It is evaporated to dryness, the residue is taken up in EtOAc and a KHSO4/K2SO4 buffer is then added. This mixture is extracted with EtOAc, then washed with saturated NaHCO3 solution and then with saturated NaCl solution; it is dried over Na2SO4 and then evaporated to dryness. The residue is triturated from Et2O, drained, washed with Et2O and dried. 6.95 g of the expected compound are obtained.
xcex1D25=+26xc2x0 (c=1, MeOH)
C) 1-[2-Amino-3-(4-cyanophenyl)propionyl]pyrrolidine trifluoroacetate, (S) isomer
6.75 g of the compound of the above step are dissolved in 50 ml of DCM and the insoluble material is filtered off. 50 ml of TFA are added and the mixture is left stirring for 45 minutes. It is evaporated to dryness, the residue is redissolved in isopropanol, this solution is again evaporated to dryness and the residue is then triturated from Et2O, drained, washed with Et2O and dried over Na2SO4. 6.13 g of the expected compound are obtained, m.p. 193-196xc2x0 C.
xcex1D25=+51xc2x0 (c=1, MeOH)
Preparation 1.13
1-[2-Amino-3-(4-cyanophenyl)propionyl]pyrrolidine trifluoroacetate, (R) isomer
A) (R)-2-(N-Boc)amino-3-(4-cyanophenyl)propionic acid
43 ml of 1N NaOH solution are added to 12.18 g of compound B of Preparation 1.11 dissolved in 180 ml of MeOH and the mixture is stirred for 1 hour at RT. 43 ml of !N HCl solution are then added and 150 ml of methanol are evaporated off, after which the mixture is taken up in EtOAc and is washed with water and then with saturated NaCl solution. 11 g of the expected compound are obtained after crystallization from an Et2O/heptane mixture.
xcex1D25=xe2x88x929.5xc2x0 (c=1; MeOH)
B) Ester of 2,5-dioxo-1-pyrrolidinyl (R)-2-(N-Boc)-amino-3-(4-cyanophenyl)propionic acid
4.2 g of NSUOH are added to 10 g of the acid obtained above dissolved in 10 ml of dioxane, followed by addition, over 20 minutes, of 8.62 g of DCC dissolved in 30 ml of dioxane. After stirring overnight at RT, the DCU formed is filtered off and washed with dioxane. The filtrate is evaporated to dryness and the residue is triturated from ether to give a solid which is filtered off and dried. 12.09 g of the expected compound are obtained.
xcex1D25=+27.1xc2x0 (c=1; MeOH)
C) 1-[2-(N-Boc)amino-3-(4-cyanophenyl)propionyl]-pyrrolidine, (R) isomer
2.6 ml of pyrrolidine dissolved in 20 ml of acetonitrile are added to 11.6 g of the compound obtained in the above step dissolved in 150 ml of acetonitrile plus 20 ml of DMF. After stirring overnight at RT, a small amount of insoluble material is removed and the filtrate is concentrated under vacuum. The residue is taken up in EtOAc and washed with KHSO4/K2SO4 solution, with saturated NaHCO3 solution and with saturated NaCl solution; after drying over Na2SO4, the EtOAc is evaporated under vacuum, the residue is triturated from ether and 9.3 g of the expected compound are obtained in the form of a white solid.
xcex1D25=xe2x88x9229.2xc2x0 (c=1; MeOH)
D) 1-[2-Amino-3-(4-cyanophenyl)propionyl]pyrrolidine trifluoroacetate, (R) isomer
8.7 g of the product obtained in the above step are stirred for 35 minutes in a mixture of 50 ml of DCM and 50 ml of TFA. After evaporating to dryness, the residue is taken up in isopropanol and re-evaporated to dryness, and 8.67 g of the expected compound are obtained in solid form.
xcex1D25=xe2x88x9246xc2x0 (c=1; MeOH)
Preparation 1.14
1-[2-Amino-2-methyl-3-(4-cyanophenyl)propionyl]-pyrrolidine trifluoroacetate
A)
A mixture of 7 g of (D,L) alanine methyl ester, 14 ml of Et3N, 4.2 g of MgSO4.3H2O and 5.1 ml of benzaldehyde in 100 ml of dichloromethane is stirred for 18 hours at RT. The insoluble material is filtered off, the filtrate is concentrated under vacuum and the residue is taken up in an ether/water mixture; the ether is separated out after settling of the phases has taken place, rewashed with water and then with saturated NaCl solution, dried over Na2SO4 and evaporated. 8.3 g of the expected compound are obtained in the form of an oil.
B)
13.2 ml of lithium bis(trimethylsilyl)amide (1M in THF) are added, at xe2x88x9270xc2x0 C. over 20 minutes, to 2.29 g of the product of the above step dissolved in 60 ml of THF. After 30 minutes, 2.35 g of 4-bromomethylbenzonitrile dissolved in 15 ml of THP are added over 15 minutes and the temperature is then allowed to rise slowly. After 3 and a half hours, the reaction medium is taken up in EtOAc and washed with water and with saturated NaCl solution. After drying and evaporating the EtOAc, 3.6 g of the expected compound are obtained in the form of an oil.
C)
The compound of the above step is taken up in 60 ml of ether plus 60 ml of 1N HCl and is stirred for 18 hours at RT. The aqueous phase is separated out after settling of the phases has taken place, placed in contact with EtOAc and brought to pH=10 with ION NaOH; the EtOAc is separated out after settling of the phases has taken place, rewashed with H2O and with saturated NaCl solution, dried and evaporated. 2.20 g of the expected compound are obtained in the form of an oil.
D)
2.42 g of Boc2O dissolved in 10 ml of dioxane are added, at 100xc2x0 C. over 10 minutes, to 2.18 g of the compound of the above step dissolved in 10 ml of dioxane; the mixture is then stirred overnight at RT and then for 3 hours at 40xc2x0 C. The reaction medium is taken up in EtOAc, washed with water and then with saturated NaCl solution, dried and then evaporated to give an oil which is used directly in the following step.
E)
The product of the above step is dissolved in 10 ml of methanol, 2.4 ml of 8.36N KOH solution are added and the mixture is stirred overnight; a further 2.4 ml of the KOH solution are added and the mixture is refluxed for 1 hour. The reaction medium is cooled and taken up in a water/ether mixture; the aqueous phase is separated out after settling of the phases has taken place, taken up in EtOAc and brought to pH=2 with 1N HCl. The EtOAc is separated out after settling of the phases has taken place, rewashed with H2O and with saturated NaCl solution, dried over Na2SO4 and then evaporated. 0.99 g of the expected compound is obtained after chromatography on silica, eluting with chloroform/MeOH/AcOH (94/6/0.2; v/v/v).
F)
0.30 ml of pyrrolidine, 1.55 g of BOP and DIPEA to obtain a pH of 6-7 are added to 0.98 g of the compound of the above step in 10 ml of DMF. After stirring for 2 and a half hours, the reaction medium is taken up in EtOAc and washed with H2O, 0.2N NaOH, 0.2N HCl, H2O and saturated NaCl solution. After drying and evaporating, 1.13 g of the expected compound are obtained, m.p.=84-87xc2x0 C.
NMR (DMSO+TFA): 1.20: s: 3H; 1.45: s: 9H; 1.60-1.90: m: 4H; 3.00-3.50: m: 6H; 7.30: d: 2H; 7.80: d: 2H.
G)
1.12 g of the compound of the above step are stirred for 1 hour in a mixture of 10 ml of DCM and 12 ml of TFA. After evaporating and drying, 1.15 g of the expected compound are obtained in the form of a solid.
Preparation 2.1
3-Amino-3-(2-naphthyl)propionic acid hydrochloride
The method described in J. Am. Chem. Soc., 1936, 58, 299 is used. 15.5 g of 2-formylnaphthalene, 10.4 g of malonic acid and 15.4 g of ammonium acetate in 150 ml of ethanol are mixed together and refluxed for 6 hours. After cooling to RT, the product is drained, washed with EtOH and dried. The product obtained is dissolved in a sufficient amount of 2N HCl and the insoluble material is then filtered off. The acidic solution is concentrated by evaporating under vacuum and the solid thus formed is recrystallized from 20 ml of an AcOH/H2O mixture (1/1; v/v). 3.8 g of the expected product are obtained.
The compounds of Table 2 below are prepared according to the procedure described above.
Preparation 2.6
3-(N-Boc)amino-3-(3,4-dichlorophenyl)propionic acid
Starting with the compound of Preparation, 2.5, the N-protected beta-amino acid is prepared in the following way.
10 g of 3-amino-3-(3,4-dichlorophenyl)propionic acid are dissolved in 100 ml of water and 9 ml of triethylamine are added, followed by gradual addition of 9.3 g of (Boc)2O in 100 ml of dioxane. After stirring overnight at RT, the medium is concentrated is and the residue is then taken up in water, adjusting the pH to 9 by addition of 1N sodium hydroxide. This mixture is washed twice with ether, the aqueous phase is taken up and acidified to pH=3 by addition of 1N HCl and is extracted with LtOAc and concentrated in order to obtain 3.9 g of the expected compound, m.p.=128xc2x0 C.
NMR (DMSO)
1.25 ppm: s: 9H; 2.50-2.65 ppm: mt: 2H; 4.75 ppm: q: 1H; 7.25 ppm: d: 1H; 7.20-7.40 ppm: m: 3H
Preparation 2.7
3-Amino-3-(3-isopropyloxyphenyl)propionic acid hydrochloride
A) (3-Isopropyloxy)benzaldehyde
3.4 g of K2CO3 and 1.5 g of benzyltriethylammonium chloride are added to 12.2 g of 3-hydroxybenzaldehyde in 100 ml of DMSO, followed by addition, over 30 minutes, of 10 ml of isopropyl iodide dissolved in 20 ml of DMSO, and the mixture is left stirring overnight at RT. The mixture is poured onto 400 ml of water and is then extracted with EtOAc, washed with saturated NaCl solution and then dried over Na2SO4 and evaporated to dryness. The oil obtained (14.4 g) is used without further purification in the following step.
B) 3-Amino-3-(3-isopropyloxyphenyl)propionic acid hydrochloride
A mixture containing 14 g of the oil obtained in the above step, 150 ml of methoxyethanol, 8.95 g of malonic acid and 13.2 g of ammonium acetate is heated overnight at 80xc2x0 C. After cooling, the mixture is evaporated to dryness and the oil formed is then dissolved in ethanol and 50 ml of 2N HCl. Fractional evaporation is carried out in order to obtain the expected compound, which is drained and then washed with EtOAc. 4.56 g are obtained.
NMR (DMSO): 1.25 d: 6H; 4.65: septet: 1H; 7.20-7.55: mt: 4H; 9.95: s: 1H.
The compounds described in the table below are prepared according to the procedure described in the above preparation.
Preparation 2.16
3-(N-Boc)amino-3-biphenyl-4-ylpropionic acid
A) 3-Amino-3-biphenyl-4-ylpropionic acid hydrochloride
18.2 g of 4-phenylbenzaldehyde, 10.4 g of malonic acid and 15.4 g of ammonium acetate in 150 ml of methoxyethanol are mixed together. After heating overnight at 80xc2x0 C., the mixture is cooled and the product formed is then washed with ethanol, with ether and then dried. After washing again with water, the product is recrystallized from a methanol/water mixture with a small amount of HCl. A mixture of the expected product and of the methyl ester hydrochloride of 3-amino-3-biphenyl-4-ylpropionic acid is obtained, which is used without further purification in the following step.
B) 3-(N-Boc)-Amino-3-biphenyl-4-ylpropionic acid
The product of the above step is placed in 200 ml of dioxane, 55 ml of 2N NaOH are added and the mixture is left stirring at RT for 1 hour 40 minutes. 13 g of Boc2O are added and stirring is continued overnight. The insoluble material is filtered off, dilution is carried out with 200 ml of water, the mixture is washed with Et2O and then acidified to pH 2.5 by addition of 2N HCl in the presence of 100 ml of EtOAc. This mixture is extracted with EtOAc, washed with KHSO4/K2SO4, with saturated NaCl solution and then dried over Na2SO4 and evaporated to dryness in order to obtain 11.03 g of the expected compound.
NMR (DMSO): 1.40: s: 9H; 2.60-2.85: mt: 2H; 5.00: dq: 1H; 7.35-7.80: mt: 10H; 12.30: bs: 1H.
Preparation 2.17
2,5-Dioxo-1-pyrrolidinyl 3-(N-Boc)amino-3-biphenyl-4-ylpropionate
3.41 g of the acid described in the above preparation are placed in 50 ml of dioxane and treated with 1.26 g of hydroxysuccinimide in the presence of 2.5 g of DCC. The mixture is left stirring overnight at RT and is then drained and washed with acetone. The filtrate is evaporated to dryness and then taken up in isopropanol. The solid is drained, washed with ether and dried to give 3.46 g of the expected compound, m.p.=161xc2x0 C.
NMR (DMSO); 1.35: s: 9H; 2.80: s: 4H; 3.00-3.20: mt: 2H; 5.00 dq 1H; 7.30-7.75 mt: 10H.
Preparation 2.18
(1,2,3,4-Tetrahydro-1-isoquinolyl)acetic acid
This compound is prepared according to J. Org. Chem., 1987, 52, 616-622.
A) 3,4-Dihydroisoquinoline
9.4 ml of 1,2,3,4-tetrahydroisoquinoline are dissolved in 200 ml of DCM and 14.7 g of NBS are gradually added. The mixture is left stirring at RT, cooling slightly in order to maintain a temperature of less than 40xc2x0 C. for 30 minutes, after which 50 ml of 10N NaOH are added and the mixture is left stirring for 1 hour at RT. The organic phase is separated out after settling of the phases has taken place and is washed with 100 ml of water and then twice with 100 ml of 4N HCl. The aqueous phases are washed with DCM and then brought to pH=9 by addition of concentrated NH4OH. This mixture is extracted with DCM, dried over Na2SO4 and evaporated to dryness. The oil obtained is distilled off. 7.16 g of the expected compound are obtained, b.p.=50-54xc2x0 C. at 0.05 mbar.
B) (1,2,3,4-Tetrahydro-1-isoquinolyl)acetic acid
A mixture containing 6.62 g of 3,4-dihydro-isoquinoline and 5.13 of malonic acid is triturated in an oil bath at 120xc2x0 C. The mixture thickens and becomes entirely solid; it is worked into a powder with a spatula. The total duration of heating is about 40 minutes. The mixture is cooled to about 60xc2x0 C. and treated with 120 ml of MeCH and 20 ml of water, which dissolves the medium. A first crop is obtained under cold conditions and a second crop is then obtained by evaporating the filtrate and crystallizing the residue from acetone.
NMR (DMSO+TFA); 2.90-3.15: mt: 4H; 3.30-3.50: mt: 2H; 4.90: t: 1H; 7.20-7.40: m: 4H.
Preparation 2.19
3-Amino-3-phenylpropionic acid trifluoroacetate, (R) isomer
A) (2-Isopropyl-5-methyl)cyclohexyl 3-(N-Boc)amino-3-phenylpropionate, (R) isomer
This reaction is carried out according to Tetrahedron Letters, 1988, 29, 6465-6466. A solution containing 11.1 g of 3-(N-Boc)amino-3-phenylpropionic acid, 7.5 g of L(xe2x88x92)-menthol and 2.1 g of DMAP in 400 ml of DCM is prepared; after stirring, 11.2 g of DCC dissolved in 50 ml of DCM are gradually introduced. After stirring overnight at RT, the mixture is filtered, the DCU is washed with acetone and the filtrate is evaporated to dryness. The residue is taken up in 150 ml of heptane at 80-90xc2x0 C.; the insoluble material is filtered off and the solution is left at RT for 4 hours. The solid is drained, washed with heptane and dried at 40xc2x0 C. until the menthol odour has disappeared. 4.25 g of the expected compound are obtained.
xcex1D25=xe2x88x926.5xc2x0 (c=1; MeOH)
B) 3-(N-Boc)amino-3-phenylpropionic acid, (R) isomer
A mixture containing 4.22 g of the compound of the above step and 15.7 ml of 1N NaOH in 100 ml of methanol is refluxed for 4 hours. The reaction medium is cooled, treated with 15.7 ml of 1N HCl and then evaporated to dryness and taken up in heptane. After leaving for a few hours at RT, the product crystallizes, it is drained, washed with heptane and then dried at 40xc2x0 C. until the menthol odour has disappeared. 2.65 g of the expected compound are obtained.
xcex1D25=+42.1xc2x0 (c=1; MeOH)
C) 3-Amino-3-phenylpropionic acid trifluoroacetate, (R) isomer
2.3 g of the compound obtained in the above step are dissolved in 15 ml of DCM and 15 ml of TFA are added. After stirring for 35 minutes at RT, the solution is evaporated to dryness. The product is taken up in isopropanol, evaporated and then crystallized from Et2O. The product is drained, washed with Et2O and dried in order to obtain 2.16 g of the expected compound.
Preparation 2.20
3-Amino-4-phenylbutyric acid hydrochloride, (S) isomer
A) Methyl 2-(N-Boc)amino-3-phenylpropionate, (S) isomer
10.8 g of methyl (L)-2-amino-3-phenylpropionate hydrochloride in 150 ml of DCM are mixed with 7 ml of Et3N and 13 g of (Boc)2O in 50 ml of DCM are gradually added. After stirring for 5 hours at FT, the reaction medium is washed with KHSO4/K2SO4 and then with saturated NaCl solution. The resulting solution is dried in order to remove the excess (Boc)2O and is then dissolved in DCM and 1.5 ml of N,N-dimethylpropane-diamine are added. After stirring for 4 hours, the mixture is washed with KHSO4/K2SO4 and then with saturated NaCl solution. This solution is dried over Na2SO4 and then evaporated to dryness in order to obtain 11.9 g of the expected compound.
B) 2-(N-Boc)amino-3-phenylpropanol, (S) isomer
This step and the following 2 are carried out according to Tetrahedron, 1994, 50(31), 9457. 10 g of the compound of the above step are dissolved in 120 ml of THF and the solution is cooled on an ice bath; 3.17 g of lithium chloride are added, followed by 2.8 g of sodium borohydride and, gradually, 170 ml of EtOH. After stirring overnight at ET, 70 ml of 1M KHSO4 are added slowly and the mixture is concentrated almost to dryness. The concentrate is diluted in chloroform and 1M KHSO4 and is then extracted with chloroform. The extracts are washed with saturated NaCl solution, dried over Na2SO4 and evaporated to dryness in order to obtain 8.65 g of the expected compound.
C) 2-Amino-3-phenylpropyl methanesulphonate, (S) isomer
7.5 g of the compound of the above step are dissolved in 40 ml of pyridine and the mixture is cooled in an ice bath; 3.3 ml of mesyl chloride are added over 15 min and the mixture is then left stirring for 2 hours at RT. 15 ml of water are added over 5 minutes and the medium is then diluted with ether and washed with 1M KHSO4 (twice), with water and then with saturated NaCl solution; the resulting solution is dried over Na2SO4 and then evaporated to dryness in order to obtain 9.2 g of the expected compound.
xcex1D25=xe2x88x9224.3xc2x0 (c=1; MeOH)
D) 3-(N-Boc)amino-4-phenylbutyronitrile, (S) isomer
A solution containing 9.05 g of the compound of the above step with 7.3 g of 18-crown-6 crown ether and 120 ml of DMSO is prepared and 9 g of potassium cyanide are added with stirring in an ice bath. After heating at 50xc2x0 C. for 5 hours, the mixture is cooled and 600 ml of Et2O are then added. This mixture is washed with water (3 times) and then with saturated NaCl solution; the resulting solution is dried over Na2SO4 and then evaporated to dryness in order to obtain 6.58 g of the expected compound.
E) 3-Amino-4-phenylbutyric acid hydrochloride, (S) isomer
This step is carried out according to Tetrahedron Letters, 1990, 31, 5153. 4.1 g of the compound of the above step are suspended in 50 ml of 6N HCl and the mixture is refluxed for 5 hours. It is concentrated in order to obtain a first crop of the pure expected compound. On evaporating to dryness, a second crop of 1.4 g of the expected compound contaminated with NH4Cl is obtained. A sample is treated with (Boc)2O and its optical rotation is measured.
xcex1D25=xe2x88x9217xc2x0 (c=1; MeOH)
literature xcex1D25=xe2x88x9216xc2x0 (c 1; MeOH)
Preparation 2.21
3-Amino-3-phenylpropionic acid trifluoroacetate, (S) isomer.
The preparation is identical to the one described in 2.19, but using D(+)-menthol
Preparation 3.1
3-Phenyl-3-(2,4,6-trichlorobenzenesulphonamido)-propionic acid
1.15 g of 3-amino-3-phenylpropionic acid are dissolved in 25 ml of dioxane and 7 ml of 1N sodium hydroxide and 1.95 g of 2,4,6-trichlorobenzenesulphonyl chloride in 5 ml of dioxane are gradually added, while maintaining the pH at 10.5-11 by addition of 1N sodium hydroxide. After stirring for 2 hours at RT, the mixture is diluted with 100 ml of water, extracted twice with EtOAc and acidified to pH=2 by addition of 6N HCl. The solid formed is drained, washed with water and dried at 40xc2x0 C. 2.09 g of the expected product are obtained, m.p.xe2x88x92218-219xc2x0 C.
NMR(DMSO+TFA): 2.60-2,95: mt: 2H; 4.75: q: 1H; 7.10-7.30: m: SH; 7.60: s: 2H; 8.85: d: 1H.
Preparation 3.2
3-(Naphth-2-ylsulphonamido)-3-phenylpropionic acid
4.13 g of 3-amino-3-phenylpropionic acid are dissolved in 100 ml of dioxane and 25 ml of 1N sodium hydroxide and 5.6 g of 2-naphthalenesulphonyl chloride are added portionwise, while maintaining the pH at 10.5-11 by addition of 1N sodium hydroxide. After stirring for 2 hours at RT, the mixture is diluted with 400 ml of water and 2N HCl is added in order to obtain pH=2. This mixture is extracted with EtOAc and the extracts are washed with a KHSO4/K2SO4 buffer, dried over Na2SO4 and evaporated to dryness. The residue is triturated from heptane and the product is isolated by decanting and is then dried under vacuum. 7.33 g of the expected product are obtained, m.p.=126-129xc2x0 C.
NMR (DMSO+TFA): 2.55-2.70: mt: 2H; 4.70: t: 1H; 6.85-8.15: m: 12H.
Preparation 3.3
2-Hydroxy-3-(naphth-2-ylsulphonamido)-3-phenylpropionic acid
This compound is prepared according to Bull. Soc. Chim., France, 1940, 593-603.
Working according to the procedures described in Preparations 3.1 and 3.2, starting with the compounds obtained in Preparation 2 and 2-naphthalene-sulphonyl chloride, the acids described in Table 4 below are obtained.
The acids described above are converted by the action of N-hydroxysuccinimide in the presence of DCC in DMF. The compounds obtained are described in Table 5 below.
Preparation 3.12
3-(2-Hydroxyphenyl)-3-(naphth-2-ylsulphonamido)-propionic acid
1.1 g of 3-amino-3-(2-hydroxyphenyl)propionic acid hydrochloride, prepared according to J. Agric. Food Chem., 1977, 25, 965, are dissolved in 25 ml of dioxane and 10 ml of 1N NaOH are added; 1.12 g of 2-naphthalenesulphonyl chloride are gradually added while maintaining the pH at 11.5-12 by addition of 1N NaOH. After stirring for 2 hours at RT, the reaction medium is diluted in water, washed with EtOAc (twice) and then acidified to pH=1.5-2 by addition of 6N HCl. The white precipitate formed is drained, washed with water and dried in order to obtain 0.82 g of the expected product, m.p.=190-200xc2x0 C.
NMR (DMSO)
2.50-3.20: mt: 2H; 4.80: mt: 1H; 6.95-8.30: m: 11H; 8.75:s: 1H.
Preparation 3.13
3-Phenyl-3-(quinol-2-ylsulphonamido)propionic acid
A) 2-Quinolinesulphonyl chloride
3.2 g of 2-mercaptocuinoline are suspended in 40 ml of water containing 0.156 g of iron trichloride. The mixture is cooled in an ice bath and chlorine is then bubbled through for 1 hour at 4xc2x0 C. The mixture is evaporated and the residue is then taken up in the minimum amount of water and the product is drained and dried in order to obtain 2.30 g of the expected compound in dry form.
B) 3-Phenyl-3-(quinol-2-ylsulphonamido)propionic acid
1.65 g of the compound prepared in the above step are dissolved in 40 ml of dioxane and 20 ml of 1N NaOH are added, along with portionwise addition of 2.27 g of 3-amino-3-phenylpropionic acid, while maintaining the pH at 10. The mixture is left stirring for 18 hours at RT and is then evaporated to dryness. The residue is taken up in a DCM/H2O mixture, the phases are separated after settling has taken place and the organic phase is extracted with water. Acidification to pH=1 is carried out by addition of HCl and the product is then drained and dried over MgSO4 in order to obtain 1.9 g of the expected compound.
NMR (DMSO+TFA): 2.4-2.9: m: 2H; 4.9: mt: 1H; 6.9-7.1: mt: 3H; 7.2: d: 2H; 7.7-8.1: m: 5H; 8.4: d: H; 8.8: d: 1H.
Preparation 3.14
3-Phenyl-3-(quinol-8-ylsulphonamido)propionic acid
This compound is prepared according to the procedure described above, starting with 8-quinolinesulphonyl chloride.
Preparation 3.15
3-(3-Isopropyloxyphenyl)-3-(naphth-2-ylsulphonamido)-propionic acid
1.3 g of the compound of Preparation 2.7 are suspended in 20 ml of dioxane and treated with 2N NaOH and then with 1N NaOH in order to bring the mixture to pH=12. 1.13. g of 2-naphthalenesulphonyl chloride are added portionwise, while maintaining the pH at 10.5-11.5 by addition of 1N NaOH. The mixture is left stirring for 2 hours at RT and is then diluted with water, washed with EtOAc and then brought to pH=2 by addition of 2N HCl. This mixture is extracted with EtOAc and then washed with a KHSO4/K2SO4 buffer and with saturated NaCl solution. The resulting solution is dried over Na2SO4 and concentrated in order to obtain 900 mg of the expected compound, m.p.=126xc2x0 C.
NMR (DMSO): 0.95: d: 6H; 2.40-2.55: mt: 2H; 4.10: tq: 1H; 4.60: dq: 1H; 6.20-8.05: mt: 11H; 8.30: d: 1H; 12.20: bs: 1H.
Following the procedure described in the above preparation, and using the compounds of Preparations 2.8 to 2.15 as starting materials, the compounds described in Table 6 below are prepared.
The acids described above (Preparations 3.15 to 3.23) are converted by the, action of N-hydroxy-succinimide in the presence of DCC in dioxane. The compounds obtained are described in Table-7 below.
Preparation 3.33
3-(3,4-Dichlorobenzenesulphonamido)-3-phenylpropionic acid
A) 3,4-Dichlorophenylbenzenesulphonyl chloride
5.4 g of (3,4-dichloro)thiophenol are suspended in 60 ml of water; 0.234 g of FeCl3 is added and chlorine is bubbled through for one hour at a temperature below 10xc2x0 C. The mixture is evaporated, drained, washed with water and then dried by azeotropic entrainment in order to obtain 6.7 g of the expected compound.
B) 3-(3,4-Dichlorobenzenesulphonamido)-3-phenyl-propionic acid
The process is then carried out according to the procedure of Preparation 3.1 in order to obtain the expected compound.
NMR (DMSO); 2.5-2.9: m: 2H; 4.6-4.8: q: 1H; 7.1: s 5H; 7.5-7.7: mt: 3H; 8.7: d: 1H; 12.4: s: 1H.
Preparation 3.34
3-(5,6,7,8-Tetrahydronaphth-2-ylsulphonamido)-3-phenylpropionic acid
A) Sodium 5,6,7,8-tetrahydronaphthalene-2-sulphonate
3.9 g of 1,2,3,4-tetrahydronaphthalene are dissolved in 10 ml of anhydrous CCl14 at 0xc2x0 C.; 4.3 g of dioxane in 10 ml of CCl4 are added, followed by 6.1 ml of sulphuric anhydride. The mixture is left stirring for 18 hours at RT and then for 3 hours at 80xc2x0 C. A water/ice mixture is added and the resulting mixture is extracted with ether. The aqueous phase is adjusted to pH=6.5 by addition of 5N NaOH. The product is drained and dried over Na2SO4 and then by azeotropic entrainment. 10.6 g are obtained.
B) 5,6,7,8-Tetrahydronaphthalene-2-sulphonyl chloride
2 g of the sulphonate obtained in the above step are mixed with 5 g of phosphorus pentachloride and the mixture is refluxed for 6 hours. It is evaporated, poured onto a water/ice mixture and then extracted with DCM, dried over Na2SO4 and evaporated in order to obtain 1.5 g of the expected compound.
C) 3-(5,6,7,8-Tetrahydronaphth-2-ylsulphonamido)-3-phenylpropionic acid
The process is then performed according to the procedure of Preparation 3.1 in order to obtain the expected product.
NMR (DMSO): 1.6-1.8: m: 4H; 2.5-2.8: m: 6H; 4.5-4.7: dd: 1H; 7-7.2: m: 7H; 7.3: d: 1H; 8.1: d: 1H; 12.3: s: 1H.
Preparation 3.35
1-(Naphth-2-ylsulphonamido)indane-2-carboxylic acid
A) Methyl (1-oxo)indan-2-carboxylate
The reaction is carried out according to J. Med. Chem., 1970, 650. A suspension of 6.75 g of sodium hydride at 80% in oil and 45 g of methyl carbonate in 120 ml of benzene are mixed together. 11.9 g of 1-indanone dissolved in 100 ml of benzene are added, at 60xc2x0 C., over 1 and a half hours and the mixture is then refluxed. After 1 hour, the benzene is distilled off. Xylene is added and the mixture is again refluxed. After 1 hour, it is cooled, 30 ml of AcOH are added and the resulting mixture is poured onto 200 ml of a water/ice mixture containing 30 ml of 1N HCl. The insoluble material is removed by filtration and the filtrate is extracted with Et2O. The extracts are washed with water, with saturated NaHCO3 solution, with water, with saturated NaCl solution and then dried over Na2SO4. The product is chromatographed on silica, eluting with EtOAc/hexane (1.3; v/v) in order to obtain 3.05 g of the expected compound,
NMR (DMSO): 3.25-3.50: mt: 2H; 3.70: ds: 3H; 4.85-4.90: mt: 1H; 7.40-7.80: m: 4H. Multiple signals since the product is partly in enolic form.
Comment: using THF as solvent instead of benzene and xylene, a better yield is obtained: 67% instead of 30%.
B) Methyl 1-hydroxyiminoindan-2-carboxylate
The reaction is carried out according to J. Heterocycl. Chem., 1974, 11, 982. 3.04 g of the compound of the above step in 9 ml of MeOH are added over 10 minutes to a mixture of 2.21 g of sodium acetate and 3.1 g of hydroxylamine hydrochloride in 3 ml of water. The mixture is then refluxed for 1 hour 30 minutes, after which it is cooled and extracted with EtOAc. The extracts are washed with water, with 3/4 saturated NaHCO3 solution, with water and with saturated NaCl solution. After evaporating off the EtOAc, 3.28 g of the expected compound are obtained in solid form.
C) Methyl 1-aminoindan-2-carboxylate hydrochloride
3.27 g of the compound of the above step are dissolved in 80 ml of EtOH, 1.2 g of 10% Pd/C are added, followed by 20 ml of 1M hydrochloric ethanol and the mixture is left stirring under a pressure of hydrogen (5 bar) at RT overnight. The catalyst is filtered off, the filtrate is concentrated under vacuum and the residue is then taken up in EtOAc and water. The water is separated out after settling of the phases has taken place and is then brought to pH=8.5 by addition of 2N NaOH. This phase is extracted with EtOAc, washed with water, with saturated NaCl solution, dried over Na2SO4 and evaporated. The residue is taken up in 20 ml of MeOH and 6 ml of 2.5N HCl. The mixture is concentrated under vacuum and the residue is then triturated from Et2O. 2.71 g of the expected compound are obtained in the form of a powder.
D) Methyl 1-(2-naphthalenesulphonamido)indan-2-carboxylate
0.91 g of the above compound is placed in 10 ml of chloroform and 0.95 g of 2-naphthalenesulphonyl chloride is then added portionwise, followed by portionwise addition of 0.68 ml of DIPEA in order to maintain the mixture at pH=7-8. After 3 hours, the reaction medium is extracted with EtOAc and then washed with 0.05N NaOH, 0.25N HCl, with water and with saturated NaCl solution. 0.99 g of the expected compound is obtained in the form of a pink-white solid.
NMR (DMSO+TFA): 2.80-3.30: mt: 2H; 3.40: s: 3H; 3.50: q: 1H; 5.10: d: 1H; 6.40-8.50: mt: 11H.
E) 1-(Naphth-2-ylsulphonamido)indan-2-carboxylic acid
0.98 g of the compound of the above step is placed in 10 ml of MeOH, 1 ml of 8.36N KOH is added, the mixture is heated at 500xc2x0 C. for 3 hours and a further 0.25 ml of 8.36N KOH is then added. After 2 hours, the medium is diluted by addition of water and EtOAc and the pH is brought to 2.5 by addition of 1N HCl. The organic phase is separated out after settling of the phases has taken place, washed with H2O, with saturated NaCl solution and then dried over Na2SO4 and evaporated. 0.80 g of the expected compound is obtained in the form of a foam.
Preparation 3.36
[2-(2-Naphthalenesulphonyl)-1,2,3,4-tetrahydro-1-isoquinolyl]acetic acid
1.91 g of (1,2,3,4-tetrahydro-1-isoquinolyl)-acetic acid (Preparation 2.18) are suspended in 25 ml of dioxane, 10 ml of 1N NaOH are added, followed by portionwise addition of 2.3 g of 2-naphthalenesulphonyl chloride, and the mixture is maintained at pH=10.5-12 by addition of 1N NaOH. The mixture is kept stirring at a constant pH for 2 hours at RT. The reaction medium is diluted with 100 ml of water and is then washed twice with EtOAc and brought to pH=1.2 by addition of 6N HCl in the presence of EtOAc. This mixture is extracted with EtOAc, washed with saturated NaCl solution, dried over Na2SO4 and evaporated to dryness. The expected product crystallizes from heptane, and is drained, washed with heptane and then dried to give 3.14 g, m.p.=132xc2x0 C.
NMR (DMSO+TFA); 2.40-2.80: m: 4H; 3.40-3.90: m: 2H; 5.45: t: 1H; 6.90-7.20: m: 4H; 7.50-8.40: m: 7H.
Preparation 3.37
The 2,5-dioxo-1-pyrrolidinyl ester of the above acid is prepared by the action of NSuOH in the presence of DCC in dioxane.
NMR (DMSO+TFA); 2.50-2.70: m: 2H; 2.75: s: 4H; 3.10-3.35: mt: 2H; 3.50-3.80: mt: 2H; 5.50: t: 1H; 6.80-8.40: m: 11H.
Preparation 3.38
3-(2-Naphthalenesulphonamido)-3-phenylpropionic acid, (R) isomer
2 g of the compound of step 2.19 are placed in 30 ml of dioxane in the presence of 7.2 ml of 2N NaOH; 1.6 g of 2-naphthalenesulphonyl chloride are added portionwise while maintaining the mixture at pH=10.5-11.5 by addition of 1N NaOH. After stirring for 2 hours at RT, the mixture is diluted by addition of 100 ml of water and is then washed with EtOAC (several times). The aqueous phase is diluted with EtOAc and then treated with 2N HCl until the pH=2.2. The resulting mixture is extracted with EtOAc, washed with saturated NaCl solution, dried over Na2SO4 and evaporated to dryness. The expected compound crystallizes from heptane, and is drained, washed with heptane and then dried. 2.2 g are obtained, m.p.=123-126xc2x0 C.
xcex1D25=+67.9 (c=1; MEOH)
Preparation 3.39
2,5-Dioxo-1-pyrrolidinyl 3-(2-naphthalenesulphonamido)-3-phenylpropionate, (R) isomer
A solution of 2 g of the above compound and 657 mg of N-hydroxysuccinimide in 35 ml of dioxane is prepared and 1.24 g of DCCI in 10 ml of dioxane are gradually added. After stirring for 5 hours at RT, the DCU is drained and washed with acetone and the filtrate is then evaporated to dryness. The residue is taken up in isopropanol. The product which crystallizes is drained, washed with Et2O and then dried. 2.18 g of the expected compound are obtained.
Preparations 3.40 and 3.41
The process is performed as in the 2 preparations described above, starting with the compound of Preparation 2.21 in order to obtain 3-(2-naphthalenesulphonamido)-3-phenylpropionic acid, (S) isomer and its 2,5-dioxo-1-pyrrolidinyl ester.
Preparation 3.42
3-(4-Chlorophenyl)-3-(2-naphthalenesulphonamido)-propionic acid, (R) isomer
A) 3-(4-Chlorophenyl)-3-(phenylacetamido)propionic acid
9.6 g of 3-amino-3-(4-chlorophenyl)propionic acid are dissolved in 200 ml of dioxane and about 50 ml of 1N NaOH in order to reach pH=10.5-11.5. The medium is cooled to +5xc2x0 C. and 6.34 ml of phenylacetyl chloride are then gradually added, while maintaining the mixture at pH=10.5-11.5 and at a temperature of between +5xc2x0 C. and +10xc2x0 C. Stirring is continued for 1 and a half hours and the medium is then concentrated to one-half before diluting with 500 ml of water. The resulting mixture is washed twice with EtOAc and then acidified to pH=1-2 by addition of 6N HCl. The solid is drained, washed with water and dried to give 14 g of the expected compound.
B) 3-Amino-3-(4-chlorophenyl)propionic acid, (R) isomer
This step is carried out according to Syn. Letters, 1993,-339. 16.8 g of the compound of the above step are suspended in 300 ml of water and 1N NH4OH is added until a pH=7.5 is obtained. 0.6 ml of Sigma penicillamidase(copyright) is added and the mixture is left stirring for 72 hours at 40xc2x0 C. The expected compound precipitates. It is drained, washed with water and with acetone and then dried at 40xc2x0 C. 2.85 g are obtained.
xcex1D25=xe2x88x925xc2x0 (c=1, 1N HCl)
C) 3-(4-Chlorophenyl)-3-(2-naphthalenesulphonamido)-propionic acid, (R) isomer
1 g of the compound obtained in the above step is dissolved in 15 ml of dioxane and 5 ml of 1N NaOH in order to reach pH=10.5-11.5. 1.15 g of 2-naphthalenesulphonyl chloride are gradually added while keeping the pH constant. After stirring for 2 hours at RT, the medium is diluted by addition of an equal volume of water and is then washed twice with EtOAc. The medium is acidified to pH=1.3 by addition of 6N HCl. This mixture is extracted with EtOAc and the extracts are washed with saturated NaCl solution (several times). The resulting solution is dried over Na2SO4 and evaporated to dryness, and the expected product then crystallizes from heptane. 1.31 g are obtained.
xcex1D25=+92xc2x0 (c=1; MeOH)
Preparation 3.43
The 2,5-dioxo-1-pyrrolidinyl ester of the above acid is prepared according to the usual technique.
Preparation 3.44
4-Phenyl-3-(2-naphthalenesulphonamido)butanoic acid, (S) isomer
1.08 g of the compound of Preparation 2.20 are dissolved in 30 ml of dioxane and 10 ml of water. 10N NaOH is added in order to reach pH=14 and 1.13 g of 2-naphthalenesulphonyl chloride are then added portion-wise, while maintaining the mixture at pH=10.5-11.5. Stirring is continued for 2 hours and the mixture is then diluted with water and washed with EtOAc. It is again diluted with EtOAc and acidified to pH=2 by addition of 2N HCl and extracted with EtOAc; the extracts are washed with saturated NaCl solution (several times) and then dried and evaporated to dryness. On addition of heptane, the expected product crystallizes. 1.25 g are obtained.
xcex1D25=xe2x88x9226.8 (c=1; MeOH)
Preparation 3.45
The 2,5-dioxo-1-pyrrolidinyl ester of the above acid is prepared using the usual techniques.
Preparation 3.46
(2S,4R) (4-(Benzyloxy)-1-(2-naphthalenesulphonyl)-2-pyrrolidinyl)acetic acid.
A) 4-(Hydroxy)-1-(2-naphthalenesulphonyl)pyrrolidine-2-carboxylic acid
2.62 g of (2S,4R)-4-hydroxyproline are dissolved in 15 ml of water containing 5.9 g of Na2CO3 and 5.21 g of 2-naphthalenesulphonyl chloride are added. After vigorous stirring for 18 hours at RT, the mixture is drained and the filtrate is then acidified to pH=1. The resulting mixture is again drained, washed with water and dried in order to obtain 4.1 g of the expected compound.
B) 4-(Benzyloxy)-1-(2-naphthalenesulphonyl)2-pyrrolidinylacetic acid
1 g of the compound of the above step is dissolved in 20 ml of DMF at 0xc2x0 C. under nitrogen; 0.204 g of sodium hydride at 80% in oil is added and the mixture is then left stirring for 1 hour at 0xc2x0 C. and for 30 minutes at RT. The mixture is cooled to 0xc2x0 C. and 10 mg of 16-crown-6 crown ether and 0.921 ml of benzyl bromide are then added. The mixture is left stirring for 1 hour at 0xc2x0 C. and then for 18 hours at 50xc2x0 C. and 10 ml of 1N NaOH are added. After stirring for 18 hours at RT, the mixture is diluted with water and then extracted with ether and acidified to pH=2 by addition of 1N HCl. The resulting mixture is extracted with EtOAc and the extracts are dried over Na2SO4 and evaporated in order to obtain 0.8 g of the expected compound.
C) (2S,4R)-4-Benzyloxy-2-hydroxymethyl-1-(2-naphthalenesulphonyl)pyrrolidine
2.8 g of the compound of the above step are dissolved in 20 ml of THF. 1.12 ml of Et3N and 0.968 ml of ethyl chloroformate are added over 30 minutes at RT, followed by addition of 0.762 g of sodium borohydride in 5 ml of water. After stirring for 20 hours at RT, the mixture is evaporated and the residue is taken up in 20 ml of water and acidified to pH=3 by addition of 1N HCl. The product is drained, washed with water, dried and then precipitated from an EtOAc/hexane mixture in order to obtain 1.9 g of the expected compound.
D) (2S,4R)-4-Benzyloxy-2-mesyloxymethyl-1-(2-naphthalenesulphonyl)pyrrolidine
3 g of the compound of the above step are dissolved in 100 ml of DCM at 0xc2x0 C. and 1.28 ml of Et3N and then 0.72 ml of mesyl chloride are added. After stirring for 30 minutes at 0xc2x0 C, a further 1.28 ml of Et3N and then 0.72 ml of mesyl chloride are added, after which the mixture is left stirring for 30 minutes at RT. It is washed, while cold, with KHSO4/K2SO4 and the insoluble material is then filtered off and the filtrate is dried and evaporated. The residue is taken up in Bt2O and used without further purification in the following step.
E) (2S,4R) 4-Benzyloxy-2-cyanomethyl-2-(2-naphthalenesulphonyl)pyrrolidine
The product of the above step is dissolved in 50 ml of DMSO, 2 g of 10-crown-6 crown ether are added and the mixture is cooled on an ice bath. 5 g of potassium cyanide are then added and the mixture is heated for 4 hours at 50xc2x0 C. The medium is diluted with 250 ml of EtOAc and is then washed with water, dried and evaporated. The residue is taken up in ether. The expected compound crystallizes and 1.7 g are obtained.
F) Ethyl (2S,4R) (4-(benzyloxy)-1-(2-naphthalene-sulphonyl)-2-pyrrolidinyl)acetate
1.6 g of the compound of the above step are dissolved in 50 ml of HCl-saturated ethanol at 0xc2x0 C. The mixture is left stirring for 48 hours at +4xc2x0 C. and is then evaporated. The residue is taken up in EtOH and evaporated (twice) and then taken up in Et2O and evaporated (twice) 20 ml of boiling water are added and a few ml of dioxane/EtCH mixture are then added to homogenize it. The solution is heated for 15 minutes at 100xc2x0 C. This mixture is evaporated and the residue is taken up in dioxane and then neutralized to pH=6 by addition of 1N NaOH. The solution is used without further purification in the following step.
G) (2S,4R) (4-Benzyloxy)-1-(2-naphthalenesulphonyl)-2-pyrrolidinyl)acetic acid
2.4 ml of SN NaOH are added to the solution of the above step and the mixture is heated at 50xc2x0 C. for 30 minutes. The solvent is evaporated off and the residue is then acidified to pH=3 by addition of concentrated HCl. The product is drained, washed with water and dried in order to obtain 1.44 g of the expected compound.
Preparation 4.1
A) N-(2-(4-(3,4-Dihydroimidazol-2-yl)phenyl)-1-((1-pyrrolidinyl)carbonyl)ethyl)-3-(3,4-dichlorophenyl)-3-(N-Boc)aminopropionamide
1.09 g of 1-[2-amino-3-(4-(3,4-dihydroimidazol-2-yl)phenylpropionyl]pyrrolidine dihydrochloride are dissolved in 15 ml of DMF, 350 xcexcl of Et3N are added and the mixture is stirred for a few minutes before adding 835 mg of 3-((N-Boc)amino)-3-(3,4-dichlorophenyl)-propionic acid (obtained in Preparation 2.6) and 515 mg of DCC.
After stirring for 3 hours, the mixture is evaporated to dryness and the residue is then taken up in methanol. The DCU is drained and the filtrate is concentrated to one-half and diluted with acetone. This mixture is filtered and then evaporated to dryness. The residue is chromatographed, eluting with a chloroform/methanol mixture (from 100/2.5 to 100/20; v/v).
B) N-(2-(4-(3,4-Dihydroimidazol-2-yl)phenyl)-1-((1-pyrrolidinylfcarbonyl)ethyl)-3-(3,4-dichlorophenyl)-3-aminopropionamide
The crude product obtained in the above step is placed in 20 ml of a solution of 4N HCl in dioxane and a sufficient amount of MeOH to allow complete dissolution. After 1 hour at RT, the mixture is evaporated to dryness and the residue is triturated twice from ether and then drained, washed with ether and dried under vacuum in the presence of KOH. 225 mg of the expected compound are obtained.
Preparation 4.2
N-[2-(4-Cyanophenyl)-1-((1-pyrrolidinyl)carbonyl)-ethyl]-3-phenyl-3-aminopropionamide trifluoroacetate, (R,R) isomer
A) N-[2-(4-Cyanophenyl)-1-((1-pyrrolidinyl)carbonyl)-ethyl]-3-phenyl-3-(N-Boc)aminopropionamide, (R,R) isomer
The 2,5-dioxo-1-pyrrolidinyl ester of the acid obtained in Preparation 2.19, step B is prepared. 800 mg of this compound are added to a mixture containing 790 mg of the compound of Preparation 1.13 in 15 ml of acetonitrile and 380 xcexcl of DIPEA. The mixture is left stirring for a few hours and is then left overnight at RT. The medium is evaporated to dryness and the residue is taken up in KHSO4/K2SO4 and then extracted with EtOAc. The organic phase is washed with saturated NaCl solution and then dried over Na2SO4 and evaporated to dryness. 1.1 g of the expected compound are obtained, this compound crystallizing from heptane.
B) N-[2-(4-Cyanophenyl)-1-((1-pyrrolidinyl)carbonyl)-ethyl]-3-phenyl-3-aminopropionamide trifluoroacetate, (R,R) isomer
1 g of the compound of the above step is dissolved in 6 ml of DCM, 6 ml of TFA are then added and the mixture is left stirring for 35 minutes at RT. The reaction medium is evaporated to dryness, the residue is redissolved in isopropanol and then evaporated, the residue is triturated from Et2O and the product is drained and dried in order to obtain 0.88 g of the expected compound.